Phenolic Constituents of the Roots of Rhamnoneuron balansae with Senolytic Activity.

With the advent of senolytic agents capable of selectively removing senescent cells in old tissues, the perception of age-associated diseases has been changing from being an inevitable to a preventable phenomenon of human life. In the search for materials with senolytic activity from natural products, six new flavonostilbenes (1-6), three new phenylethylchromanones (7-9), three new phenylethylchromones (10-12), and four known compounds (13-16) were isolated from the roots of Rhamnoneuron balansae. The chemical structures of these isolated compounds were determined based on the interpretation of spectroscopic data, including 1D and 2D NMR, ECD, and HRMS. The absolute configuration of compound 1 was also determined by a Mosher ester analysis and ECD calculations. Compounds 6-8 were shown to selectively destroy senescent cells, and the promoter activity of p16INK4A, a representative senescence marker, was reduced significantly by compound 6. The present results suggest the potential activity of flavonostilbene and phenylethylchromanone skeletons from R. balansae as new senolytics.